Transitions can be difficult at any age; however, the move from elementary school to middle school, coupled with the onset of adolescence, is often associated with a myriad of psychological and academic declines. One strategy currently used to "ready" elementary students for middle school is a departmentalized organizational structure. The purpose of this study was to investigate young adolescents' self-concept and classroom environment perceptions as they transitioned from two different elementally organizational structures into one middle school. Data were collected from 125 fifth-grade students who participated in a middle school transition program. Findings suggest that participants' perceptions of self-concept and classroom climate did not differ prior to or after the transition to middle school, based on the elementary organizational structure they experienced. However, time effects suggest that students' self-concept did significantly increase across the transition to middle school, while their perceptions of classroom climate were mixed. (Contains 8 tables.)